Watch manager Richard Chamberlain said the detector would have raised the alarm at least 30 minutes earlier.

A man who lives upstairs from Ms Marriott said after calling 999 the passer-by who spotted the blaze banged on the doors of the other eight residents in the red brick three-storey block.

Smoke logged

The neighbour said: “I rushed down and the door was open but there was a big dog going mad behind the door so we couldn’t get in.

“The fire brigade was there minutes later. When two fire fighters brought her out I was convinced she was dead, but they did CPR and she was sitting up in the ambulance.”

Watch manager Richard Chamberlain said: “The fire was dying down when we got there but the room was very heavily smoke logged. It had been quite a severe fire.

“The injuries were life threatening. She was in a very bad way when we got her out. She had severe smoke inhalation and burns to her legs.”

Another neighbour described Ms Marriott, who was in a critical but stable condition last night, as a “lovely lady”.

Mr Chamberlain said their rescue efforts were seriously hampered by cars.

He said: “Parked cars had to be almost pushed out of the way by our fire appliance, which was also damaged, to get to the incident.

“People really need to think about where they park because it delayed us getting crews into the building by five minutes.

“Cars weren’t illegally parked but inconsiderately parked on both sides of the road with room only for a small car.

“People need to think – next time it could be their house going up in flames or their relatives trapped inside.

“Lives are at risk and every minute counts. It’s frustrating and happens in Brighton all the time.”

One local resident said parking in the area was a nightmare, adding: “At night it’s terrible. Even small cars struggle to get through.”

Fire crews were forced to park 300 metres away when a schoolboy was trapped inside his burning family home in Toronto Terrace, Hanover, in December 2010.

Smoke alarms

And in January 2009 crews struggled to reach a home in St Mary Magdalene Street after three-year-old Stanley Townsend turned on a cooker, accidently starting a blaze.

A council spokeswoman said the council was not legally obliged to install smoke alarms in all council flats.

She said: “At this time we are concerned foremost with the welfare of the tenant.

“Regarding fire safety, current government guidance for purpose built blocks of flats does not require a fire alarm system to be fitted in the common way. “There is no legislation that requires fire detector systems to be fitted inside a unit of accommodation used as a single private dwelling but it is council policy to fit smoke alarms when properties are refurbished and rewired and many flats in council owned blocks do already have these.

“We work in partnership with East Sussex Fire and Rescue Service which is able to carry out home safety visits and fit smoke detectors where necessary, free of charge.”

An East Sussex Fire and Rescue Service spokesman added that it could not be confirmed who would be liable for the damage to the vehicles as it would be dealt with on a case-by-case basis.